Ascariasis in Dogs

Ascariasis is a disease affecting dogs caused by the intestinal parasitic roundworm (or Ascaris lumbricoides). Roundworms are often quite large -- up to 10 to 12 centimeters in length -- and can be present in extremely high numbers within an infected animal. When they are found in a dog's body, it can lead to abdominal swelling (distension), colic, gastrointestinal issues and even intestinal rupture.

The condition or disease described in this medical article can affect both dogs and cats. If you would like to learn more about how this disease affects cats, please visit this page in the PetMD health library.

Symptoms

The following signs or symptoms are common in dogs that have roundworms:

• Colic
• Lethargy
• Vomiting
• Abdominal swelling
• Abnormal feces
• Poor nursing (in females)
• Anorexia
• Coughing (caused when the roundworm larvae have migrated into the dog's lungs)

Causes

Adult dogs can become infected through the ingestion of roundworm eggs, which are found in infected food, water, vomit, or feces. Pups can then contract the parasite during the pregnancy or by drinking the milk from an infected pregnant animal. And if one of the newborns in a litter is exposed to roundworms, the entire litter can contract the parasite.

Diagnosis

Upon examination of the dog, a swollen abdominal region is commonly detected. There may also be signs of weakness and loss of appetite. A fecal swab will then be taken to detect the presence of roundworm eggs. Dead roundworms being passed out of the animal's body is another good indicator of the disease.